Process of molding faced concrete units



Patented Mar. 26, 1929.

WILLIAM EOSGOE TUCKER, OF DAWSON'VILLE, GEORGIA.

PROCESS OF MOLDING FACED CONCRETE UNITS.

No Drawing.

This invention pertains to the molding of concrete units having projecting sunkenjointed faces, and has for its object the most economical and practical production of concrete units of this kind.

In molding a faced concrete unit by this process where irregular broken stones, sized rock screenings, and water-soluble glue are used, respectively, as facing material, filling material, and adhesive substance, the stones a re placed lace-down on the bottom of the mold in the positions that they are to occupy in the face oli thev finished unit, and the spaces between the stones are filled with screenings to a somewhat greater death than that wnich the face joints are to have.

The bottom part of the mold, bearing the stones and screenings, and maintained in a level position, is now lowered into a thin glue solution, where it is allowed to remain until the solution, rising; tl'u'ough the perito one in the bottom of the mold, suhincrges the portion of the stones that are to show in the face at the finished unit, and also covers the screenings to the same level.

The work is next raised from the solution, the stones and screenings allowed to drain and dry, and all screenings not attached by the glue dumped by partly inyerting the worlc.

'lhc voids lytween the screenine's may now be filled and a tighter surface (mtained, if desired, by shaking); in finer screenings, uiul retrieving the surplus tine screenings by directing: a current oi? air downward against the work;

The mold is ne1t assembled and in order to aid adhesion betwecnthe fresh concrete mixture and the stones and scrcenii it is \Yoll exposed surfaces of the to wet uh storms and screenings by tog-spraying with Water,

ll here a facing mixture and a backing mixture are used, the facing mixture is first applied and worked well. in between the stones and against the screenings, after which the mold is filled with the backing mixture, and the unit is left to harden.

In molding concrete units having more than one face, by this process, the part, or parts, of the mold coveringsuch additional 011 the bottom of the mold, fillin Application filed February 18, 1928. Serial No. 255,496.

face, or faces,is treated just as outlined for the bottom part of: the mold, until the mold is ready for assembling, when a layer of the facing mixture is applied, like plaster, to the additional face, or faces, in order to hold. the finer screenings in place, after which. the mold is assembled, partitions are inserted parallel to the faces being treated, and the remainder of the facing mixture appliet lVhen the unit i 5 ha rd enough to withstand handling the face, or :taces, are soaked in water, or are stcamcr'l, until the glue is thoroughly softened, the mold is removed, the g rlic and loose screei'lings washed oil, and curing of the unit continued in the usual manner.

This process excels all others for the molding of concrete units of this kind, in that the glued screenings perform the tour services o'l (first) holding the facing stones in position until the unit lmrdens, (second) protecting the exposed portion of the faci115;- stones from the fresh facing mixture, (third) regulating the depth of the taco joints, and (fourth) giving to the sulrtace of the unit, or back Walls of the lace joints, a close rocktextured finish.

l urthermore, concrete units made by this process present a unique and pleasing appearance, possess the light and shade e'llect which adds so much to the beauty and rel'lllGlllQ-Hl; of buildings, and, by the use of selected materials, can be made as varied, artistic, and colorful as desired,

1 claim:

The process oil molding; laced concrete units consisting in Pltlt'illlfl' the facing stones ,0; the spaces between the stones with a suitable filling material, as rock screenings; suluuerging tllo stones and scrcenhmy-z to the desired level in a solution ol a suitable adhesive sub stance, as glue; draining and drying the submerged portion of the stones and screenings; eliminating all unattached screenings; and filling the mold with the facing, and backing concrete mixtures, substantially as herein described.

WIELIAM ROSCOE TUCKER. 

